Question

The student plans to conduct a spectrophotometric analysis to determine the concentration of Cu2+(aq) in a solution. The solution has a small amount of Co(NO3)2 (aq) present as a contaminant. The student is given a diagram below, which shows the absorbance curves for aqueous solutions of Co2+ (aq) and Cu2+ (aq)
c. The spectrophotometer available to the student has a wavelength range of 400 nm to 700 nm. What wavelength should the student use to minimize the interference from the presence of the Co2+ (aq)?

Answer 1

Answer:

The wavelength the student should use is 700 nm.

Explanation:

Attached below you can find the diagram I found for this question elsewhere.

Because the idea is to minimize the interference of the Co⁺²(aq) species, we should choose a wavelength in which its absorbance is minimum.

At 400 nm Co⁺²(aq) shows no absorbance, however neither does Cu⁺²(aq). While at 700 nm Co⁺²(aq) shows no absorbance and Cu⁺²(aq) does.

Answer 2

Answer:

Spectrophotometric analysis is a quantitative measure of the interaction of spectrum rays and certain molecules.  The wavelength used by student is 700 nanometers.

Explanation:

Spectrophotometric analysis is a method used to measure the amount of absorbance or transmittance done by a substance.

From the knowledge of spectrometric analysis:

• Copper is absorbed at 700 nanometers.
• Cobalt is absorbed between 400-500 nanometers.

In the given question, to minimize the interference by cobalt ion, the student should use the wavelength of 700 nanometers or more. The copper is absorbed at wavelength of 700 nm or more, whereas the cobalt ion is absorbed between the range of 400 to 500 nanometres.

Therefore, the student will use wavelength of 700 nanometers because copper is absorbed at this wavelength. The cobalt is absorbed at 400 to 500 nanometers, which will minimize its interference.

For Further Reference:

https://brainly.com/question/22367058?referrer=searchResults